Hip abductor tears(AT) have long been under-recognized, under-reported and under-treated. There is a paucity of data on the prevalence, morphology and associated factors. Patients with “rotator cuff tears of the hip” that are recognized and repaired during total hip arthroplasty(THA) report comparable outcomes to patients with intact abductor tendons at THA.

The study was a retrospective review of 997 primary THA done by a single surgeon from 2012–2022. Incidental findings of AT identified during the anterolateral approach to the hip were documented with patient name, gender, age and diagnosis. The extent and size of the tears of the Gluteus medius and Minimus were recorded. Xrays and MRI's were collected for the 140 patients who had AT and matched 1:1 with respect to age and gender against 140 patients that had documented good muscle quality and integrity. Radiographic measurements (Neck shaft angle, inter-teardrop distance, Pelvis width, trochanteric width and irregularities, bodyweight moment arm and abductor moment arm) were compared between the 2 groups in an effort to determine if any radiographic feature would predict AT.

The prevalence of AT were 14%. Females had statistically more tears than males(18vs10%), while patients over the age of 70y had statistically more tears overall(19,7vs10,4%), but also more Gluteus Medius tears specifically(13,9vs5,3%). Radiographic measurements did not statistically differ between the tear and control group, except for the presence of trochanteric irregularities. MRI's showed that 50% of AT were missed and subsequently identified during surgery.

Abductor tears are still underrecognized and undertreated during THA which can results in inferior outcomes. The surgeon should have an high index of suspicion in elderly females with trochanteric irregularities and although an MRI for every patient won't be feasible, one should always be prepared and equipped to repair the abductor tendons during THA.

We have developed a technique with the underlying principle being that the difference in height between what is removed and what is inserted will determine the leg length correction (Figure 1). The height of the implant to be inserted is determined from the manufacturer's specifications. We have developed a Vertical Measurement Tool to accurately and reproducibly determine the height of the resected bone (Figure 2).

Leg length correction = a−b−c+d

Vertical Measurement Tool validation was performed by 4 separate surgeons on 20 resected femoral heads in the laboratory. Inter and intra-observer error was assessed. Fifty patients were assessed clinically and radiologically, to assess if desired leg length correction was achieved.

Statistical analysis showed the device to be accurate with high intra and inter observer reliability. Differences between the observers were tested using a general linear model in a repeated measure design. No main effect and interaction effects were found. Intra operatively the resected head was measured and the formula was applied. The range of desired correction was 0mm to 18mm. In all cases the post-operative correction was within 4mm of the pre-operative planned correction. Statistical analysis showed that a linear Regression with ‘Actual’ as dependent and ‘Lambda’ as independent variables resulted in R= 0.889.

We believe that it is consistently possible to achieve a leg length correction to within 5 mm of the pre-operative plan using the Vertical Measurement System. The system is simple and reproducible even in the hands of relatively inexperienced surgeons.

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Introduction:

The ASR™ Articular Surface Replacement and ASR™ XL Metal-on-Metal systems were recalled due to high revision rates at five years. A worldwide clinical follow-up of patients was initiated. This paper summarizes current findings in South Africa (SA) in comparison with those outside SA (OSA).

Background

Rapid mobilisation programs, or “fast track” protocols, are aimed at shorter hospital stays. We found a limited local experience with these programs in total hip arthroplasty in South Africa, and decided to introduce a pilot study at our institution.

Background and Purpose of Study

The Valgus knee in total knee Arthroplasty, is considered a more demanding procedure, often with ligament balance a greater challenge than seen with neutral or Varus knees. It has also frequently been suggested that prostheses with higher levels of constraint be used to avoid late-onset instability. Various lateral release techniques have also been suggested in the literature.

This study is aimed at assessing the outcomes of an unconstrained, rotating platform designed prosthesis, the LCS, using our technique, in the management of severe valgus deformity.

Purpose of study

To determine the onset, incidence and associated symptoms of adverse noise emissions following total hip arthroplasty (THA) with ceramic-on-ceramic (CoC) bearing surfaces

Introduction

The deltamotion bearing system provides a large bearing even with small acetabular components. With optimally placed components the risk of dislocation is extremely low. However the acetabular component is a monobloc system and has significant technical considerations. This is an early series of patients to determine whether a monobloc system can be reliable placed in an acceptable position

Purpose of Study

To assess the results of Revision Hip Surgery in which a less invasive technique was utilized in situations where a number of different options was available.

Heterotopic ossification (HO) is a common complication following total hip replacement with a number of papers reporting an incidence of greater than 40%. In an effort to reduce the degree of contamination of the abductor muscle bed with osteoprogenitor cells, we used a plastic protective shield during the preparation and reaming of the femoral head in the hope that this would result in a decreased incidence of HO.

One hundred and forty consecutive metal-on-metal resurfacing procedures (mean age 52.3 years) utilizing the Birmingham hip prosthesis were performed between March 1999 and May 2002. Pre-operative diagnosis included osteoarthritis (105), Dysplasia (19), AVN (8), Inflammatory arthropathy (8). In the first 70 cases wet swabs packed around the femoral head were used in an attempt to reduce bone contamination. For all subsequent cases, bone contamination was controlled by the use of the plastic shield. Patients were reviewed clinically and radiologically at a mean of 36.1 (range 24–62) months post operatively. Pre-operative and follow up radiographs were assessed for presence of HO according to the Brooker classification. Harris hip and UCLA activity scores were recorded pre- and post-operatively on all patients. Three patients were lost to follow up.

Eighteen patients (12.9%) were noted to have HO on follow up radiographs. Sixteen patients in the initial group when no shield was used developed HO (Brooker I [10], II [2] & III [1]). Only two patients developed HO (Brooker I) following introduction of the protective shield. This modification in surgical technique was statistically significant in decreasing incidence of HO. All patients with radiological abnormalities were asymptomatic. We propose that this protective shield should be used during resurfacing hip arthroplasty as prophylaxis against ectopic new bone formation.

Introduction and Aims: We undertook this study to detemine the results of acetabular fixation using the Duraloc 300 uncemented acetabular component combined with impaction bone grafting in patients with acetabular protrusion.

Method: Thirty consecutive total hip replacements using a Duraloc 300 cup in patients with acetabular protrusion requiring impaction bone grafting were reviewed at an average of 5.2 years. Pre-operative x-rays were analysed for degree of protrusion. Post-operative x-rays were analysed for cup placement and interface gaps. Follow-up films were analysed for graft incorporation, lucent lines, osteolysis, wear and migration. Kaplan-Meier survivorship analysis was performed.

Results: All components were found to be stable with no evidence of loosening or migration. All but two cases showed trabeculated bone with an average minimum thickness of 7mm of bone medial to the cup in zone 2. Mean rate of wear was 0.10mm per year. No cases of pelvic osteolysis were seen.

Conclusion: The Duraloc 300 cup provides excellent fixation in patients with acetabular protrusion and impaction bone grafting. The graft has been found to incorporate and remodel. We are therefore optimistic that the durability of fixation should equal that of primary hip surgery without protrusion.

Introduction and Aims: We undertook this study to detemine the results of acetabular fixation using the Duraloc 300 uncemented acetabular component in patients with inflammatory joint disease and poor bone stock.

Method: Fifty consecutive total hip replacements using a Duraloc 300 cup in patients with imflammatory joint disease were reviewed at an average of 8.2 years. Postoperative x-rays were analysed for cup placement and interface gaps. Follow-up films were analysed for lucent lines, osteolysis, wear and migration. Kaplan-Meier survivorship analysis was performed.

Results: All components were found to be stable with no evidence of loosening or migration.

One patient developed sepsis seven years post-surgery. There was no evidence of excessive wear or osteolysis.

Conclusion: The Duraloc 300 cementless acetabular component has excellent fixation with no cases of loosening at an average of 8.2 years in patients with inflammatory joint disease. The low rate of wear and pelvic osteolysis may be indicative of the decreased demands placed on the prosthesis in this cohort of patients. The poor bone stock has not however adversely effected acetabular fixation.

Introduction and Aims: Eight thousand Duraloc 300 cups were implanted worldwide in 2002. To our knowledge, no 10-year results have been published to date. We undertook this study to ascertain whether this optimism was justified.

Method: One hundred consecutive total hip replacements using a Duraloc 300 cup were reviewed at a minimum of 10 years. Post-operative x-rays were analysed for cup placement and interface gaps. Follow-up films were analysed for lucent lines, osteolysis, wear and migration.

Kaplan-Meier survivorship analysis was performed.

Results: All components were found to be stable with no evidence of loosening or migration. The mean rate of wear was 0.12mm per year. Three hips developed pelvic osteolysis in zone 2 at the level of the apex hole, of which two have successfully undergone a bone grafting procedure and one patient is awaiting surgery.

Conclusion: The Duraloc 300 cup has excellent 10-year results with no cases of loosening. There was a low incidence of pelvic osteolysis. Cementless fixation provides dynamic biological fixation, which is continuously renewed with the passage of time. There is no reason to believe that the durability of fixation will not extend well beyond 10 years.

We reviewed 19 patients (30 feet) with congenital vertical talus treated surgically between 1987 and 1999, 22 of them by the same surgeon.

The etiological diagnosis was idiopathic in seven patients. Six patients had associated congenital abnormalities (four arthrogryposis, two digitotalar dysmorphism) and six had associated neurological abnormalities (three microcephalic, three spinal dysraphism). Only two patients had surgery after the age of 18 months. The mean age at surgery was 14.7 months (6 to 51).

In 15 feet a two-stage procedure was performed. Lengthening of the extensor tendons, notably tibialis anterior, was followed six weeks later by posterior release. In 15 feet a one-stage procedure was done, with no lengthening of the extensors or transfer of tibialis anterior. The Kidner procedure was done in seven feet, but the tibialis posterior was never found to be subluxed and the procedure was abandoned. The calcaneocuboid joint was opened and pinned in eight feet. The peroneal tendons required lengthening in eight feet.

At a mean follow-up of 5.8 years (2 to 13.5), results were excellent in 17 feet (normal forefoot and hind-foot). Results were good in seven feet (normal radiographs, normal hindfoot, but pronated forefoot). In four feet the result was fair (valgus hindfoot with a plantarflexion angle of the talus more than 35(). In one patient, the results in both feet were poor (uncorrected).

All seven good results followed a two-stage procedure. We concluded that this was due to relative weakening of the lengthened tibialis anterior to the peroneus longus. Where necessary, plantarflexion of the talus should be corrected at operation, and this should be correlated with intra-operative fluoroscopy. Adequate reduction of the navicula inferomedially on the talar head obviates the need for tendon transfer.